----- "Peter Stuge" peter@stuge.se wrote:
Nasa wrote:
All that said, I was hoping to get pointed in the right direction to being able to install this in my motherboard. The specifics of the board (in case I misread the post) are(from manual):
IBASE MB899 Intel 945GM Chipset GMCH: 82945GM 1466-pin Micro-FCBGA ICH7M:82801GBM 652-pin MBGA.
Did you pick a particular CPU for the board, or did the CPU come already installed when you bought the board?
In general you're in luck because as was noted the board is supported by coreboot.
You will need a few things:
- Cross-over serial cable (AKA null modem)
- Spare boot flash chips
- Patience
You have to choose a payload for your coreboot build. coreboot does hardware init but does not include any code to boot your operating system. That second part is handled by a completely separate program, which is stored together with coreboot in the boot flash.
An easy first step might be to use SeaBIOS as payload. SeaBIOS is an open source legacy BIOS implementation, so your system should start just like before. Once everything is running well with coreboot+SeaBIOS you could move on and try to optimize the boot even further, using other payloads.
While I am very capable of building software out of SVN (been doing that for mythtv, openmobile, etc) and linux kernel,
Good. Note that coreboot and SeaBIOS both run before an operating system environment is available, and the toolchains shipped with many distributions have been patched so that they fail to correctly build such software. You can try using your regular toolchain, but if you have any trouble then it is recommended to build a reference toolchain and use that to build coreboot. After svn checkout of the coreboot tree, do:
cd util/crossgcc ./buildgcc cd ../.. rm -f .xcompile
The next time you run make in the coreboot directory it should pick up the toolchain built by buildgcc automatically. Check the contents of .xcompile to make sure.
I have not played with pulling individual chips, like a BIOS. So I don't know anything about acquiring and/or replacing one.
Note that BIOS is the software, not so much the flash chip it is stored in.
You will need replacement flash chips. They shouldn't cost more than a few USD and I recommend getting a few of them, so that you always have at least one backup of the factory BIOS that you can use if coreboot doesn't work straight away. (Sometimes it will, but better safe than sorry, if there's a problem you can't start the system anymore without a backup flash chip.)
Warren Turkal wrote:
the bios chip might be the SST thing near the white connector in the bottom left quadrant of the board.
Yes, that's correct. This package is called PLCC32, but only describes the physical format of the chip.
I think it's an LPC style chip.
Well, almost. It is connected to a bus which is electrically and protocol-wise compatible with LPC, but all Intel chipsets use their own memory read and write commands which are different from the LPC standard commands. The flash chip type is usually called FWH, Firmware Hub, since that is the name of Intel's own boot flash chips.
Look for a couple of compatible flash chips. Some current part numbers are:
8Mbit = 1Mbyte SST49LF008A-33-4C-NHE http://parts.digikey.com/1/parts/1904170-ic-flash-fwh-8mbit-33mhz-32plcc-sst...
16Mbit = 2Mbyte SST49LF016C-33-4C-NHE SST49LF016C-66-4C-NHE http://parts.digikey.com/1/parts/1904173-ic-flash-ser-lpc-16mbit-32plcc-sst4...
You can most likely use flashrom (flashrom.org, coreboot sibling project) to read the factory BIOS from the chip in a running system. You can then hotswap flash chips (prepare them with pushpin knobs first) in the running system, put a blank chip in, and write your first factory BIOS backup onto that. Then get the third flash chip, repeat the hotswap, and write a coreboot image with SeaBIOS onto that chip. Reboot and watch the seral port output on another computer, via the null modem cable.
//Peter
Wow,
Thanks a lot Peter -- that was VERY informative.
I choose the CPU (a number of years ago) which is an Intel Core 2 Duo Mobile 1.66GHz.
I have read a little about payloads and noted that SeaBIOS would be the easiest way to go... However (this being important for the flash chip), I didn't see anything about the benefits of putting a linux kernel as a payload. I did read from the FAQ that most chips aren't large enough to have the kernel added as a payload. If my goal is the fastest boot time possible, while still supporting the basic system, would going to a Linux payload be the way to go? If so, what size flash chip should I get?
Thanks Again for the SWEET email.
Nasa
BTW: once I get this working, it's going up on the carpc forum -- I know a lot of people would be interested in reducing their systems boot time.
-
Nasa